Mucositis is the medical term for the painful inflammation and ulceration of the mucous membranes lining the digestive tract. Mucositis often appears as an adverse effect of chemotherapy and radiotherapy treatment for cancer. Mucositis can occur anywhere in the body where mucous membranes are present but is most common in the gastrointestinal tract and oral cavity. Oral mucositis refers to the inflammation and ulceration that occurs in the mouth and is a common and often debilitating side-effect of cancer treatment. Oral mucositis is generally graded on a WHO scale ranging from 1 to 4, 4 being the most severe. In grade 3 oral mucositis, the patient is unable to eat solid food, and in grade 4, the patient is unable to consume liquids as well.
Oral and gastrointestinal mucositis can affect up to 100% of patients undergoing high-dose chemotherapy and hematopoietic stem cell transplantation (HSCT), 80% of patients with malignancies of the head and neck receiving radiotherapy, and a wide range of patients receiving chemotherapy. Alimentary tract mucositis increases mortality and morbidity and contributes to rising health care costs.
For most cancer treatment, about 5-15% of patients get mucositis. However, with 5-fluorouracil (5-FU), up to 40% get mucositis, and 10-15% get grade 3-4 oral mucositis. Irinotecan is associated with severe GI mucositis in over 20% of patients. 75-85% of bone marrow transplantation recipients experience mucositis, of which oral mucositis is the most common and most debilitating, especially when melphalan is used.
Radiotherapy to the head and neck or to the pelvis or abdomen is associated with Grade 3 and Grade 4 oral or GI mucositis, respectively, often exceeding 50% of patients. Among patients undergoing head and neck radiotherapy, pain and decreased oral function may persist long after the conclusion of therapy. Fractionated radiation dosage increases the risk of mucositis to more than 70% of patients in most trials. Oral mucositis is particularly profound and prolonged among HSCT recipients who receive total-body irradiation.
Present treatment of mucositis is mainly supportive. Oral hygiene is the mainstay of treatment; patients are encouraged to clean their mouth every four hours and at bedtime, more often if the mucositis becomes worse. Water-soluble jellies can be used to lubricate the mouth. Salt mouthwash can soothe the pain and keep food particles clear so as to avoid infection. Medicinal mouthwashes may be used such as Chlorhexidine gluconate and viscous Lidocain for relief of pain. Palifermin is a human KGF (keratinocyte growth factor) that has shown to enhance epithelial cell proliferation, differentiation, and migration. Experimental therapies have been reported, including the use of cytokines and other modifiers of inflammation (e.g. IL-1, IL-11 and TGF-beta3), amino acid supplementation (e.g. glutamine), vitamins, colony-stimulating factors, cryotherapy, and laser therapy. Symptomatic relief of the pain of oral mucositis may be provided by barrier protection agents such as concentrated oral gel products (e.g. GELCLAIR™). CAPHOSOL™ is a mouth rinse which has been shown to prevent and treat oral mucositis caused by radiation and high dose chemotherapy. A problem with many of the barrier protection agents is that very frequent application may be required, often as many as 4-10 times per day.
Sores or ulcerations can become infected by virus, bacteria or fungus. Pain and loss of taste perception makes it more difficult to eat, which leads to weight loss. Ulcers may act as a site for local infection and a portal of entry for oral flora that, in some instances, may cause septicemia (especially in immunosuppressed patients). Approximately half of all patients who receive chemotherapy develop such severe oral mucositis that becomes dose-limiting such that the patient's cancer treatment must be modified, compromising the prognosis.” Thus, there is still a pressing need for improved methods for preventing and treating mucositis.